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Changes between Version 1 and Version 2 of Ticket #7274

v1	v2
1	1	Zach observed that the Mac distribution dmg file (.dmg) can be made much smaller (60% of dmg size) using instead an LZMA compressed tar file (.tar.xz made with tar -cfJ), ticket #7250 comment 13. This would reduce our 400 Mbyte Mac distribution to about 240 Mbytes.
2	2
3		The dmg format supports LZMA compression but only from macOS 10.15 onward, and testing it gave dmg size that was 70% of the current dmg (which uses zlib level 1 compression). But we currently distribute on macOS 10.14. I tested on our build machine essex.cgl.ucsf.edu and the LZMA compressed dmg indeed fails to mount (error is "corrupted file", using command "hdiutil attach cx1.4_lzma.dmg").
	3	The dmg format supports LZMA compression but only from macOS 10.15 onward, and testing it gave dmg size that was 70% of the current dmg (which uses zlib level 1 compression). But we currently distribute on macOS 10.14. I tested on our macOS 10.14 build machine essex.cgl.ucsf.edu and the LZMA compressed dmg indeed fails to mount (error is "corrupted file", using command "hdiutil attach cx1.4_lzma.dmg").
4	4
5	5	This does not seem like a good enough reason to drop 10.14 support. We could provide two dmg files one for 10.14 and one for 10.15 and later. We'd want the download page to only show the appropriate file. That can only work if the user agent identified by the web browser on 10.14 identifies the OS vesion as 10.14. Have to check if it does.